Huntron alternating input channel circuit using 555 timer. Manually select channel or 0.8 Hz output to solid state dry reed relay like 835-c. Red led A channel indicator. Yellow led B channel indicator. Switch down for A, up for B. Both to no connection for auto alternate. This is to simulate 3 position switch. Useful with component tester, (octopus tester), to compare good component to DUT.
